Gear grinding machine



Aug. 25, 1942. ORCUTT 2,294,045

GEAR GRINDING MACHINE Filed July 12, 1940 5 Sheets-Sheet l Ora-x142 Aug.25, 1942. A. H. ORCUTT GEAR GRINDING MACHINE Filed July 12, 1940 5Sheets-Sheet 2' Aug. 25, 1942. A. H.-ORCUTT GEAR GRINDING MACHINE Filedy 2, 1940 5 Sheets-Sheet 5 Aug. 25, 1942, A. H. ORCUTT GEAR GRINDINGMACHINE Filed July 12, 1940 5 Sheets-Sheet 4 Fig.4

Aug. 25, 1,942. A. R T 2,294,045 GEAR IGRINDIING MACHINE Filed Jul 12,1940 5 She eps-Sheet s Jim i Patented Aug. 25, 1942 UNHED TES NT OFFICEGEAR GRINDING MACHINE Application July 12, 1940, Serial No. 345,243 InGreat Britain July 22, 1939 4 Claims.

This invention has for its object to provide an improved machine forgrinding to the required forms the teeth of so-called helical gearwheels.

The invention comprises the combination of a frame, a horizontallymovable slide carrying a member on which a formed grinding wheel can beadjustably mounted and which is angularly adjustable about a verticalaxis to enable the central plane of the grinding Wheel to be moved toany desired position relatively to the axis of the work piece, areciprocatory saddle for carrying the work piece, means for impartingoscillatory movements to the work piece during the reciprocatorymovements, and a grindingwheel trimming mechanism which is horizontallyslidable and angularly adjustable about a vertical axis- The inventionalso comprises the combination of a spindle on the saddle which operatesthe work piece, a pair of reciprocatory members operatively connected tothe spindle, and a pair of ramps angularly adjustable on the frame, theramps serving to impart through the medium of the said reciprocatorymembers opposite angular movements to the spindle during thereciprocation of the work piece relatively to the grinding wheel.

In the accompanying sheets of explanatory drawings:

Figure 1 is a front elevation, Figure 2 a plan, and Figures 3 and 4opposite end elevations of a gear grinding machine constructed inaccordance with the invention.

Figure 5 is a fragmentary part sectional end view illustrating to alarger scale than Figures 1 to 4, the means for imparting oscillatorymovements to the work piece.

In carrying the invention into effect as shown, I employ a rigid framecomprising a. base a, end columns I), and an upper transverse member 0.On the base a is mounted a bed d carrying a horizontally reciprocablesaddle e which is adapted to be actuated by for example, hydraulic meansas 1 also carried by the bed. Onthe saddle e is mounted a headstock hand a tailstock i which support opposite ends of a horizontal spindle 11for carrying and actuating the work piece It.

For imparting the required oscillatory movements to the spindle j duringthe reciprocation of the work piece R: with the saddle e relatively tothe grinding wheel 122, there is mounted in the headstock h a hollowspindle 11. within which is arranged another spindle 0. One end of the55 latter spindle is connected in any convenient manner to the adjacentend of the work spindle a. At their ends remote from the work spindle 7'the two spindles n, o are interconnected by any suitable mechanism (notshown) which is arranged in the headstock h and enables the requiredindexing movements to be imparted to the work spindle, an example ofsuch mechanism being described in the prior Patent Specification No.2,066,220. On the hollow spring 11 is mounted a pinion p which isengaged at its 'opposite sides by a pair of vertically slidable racks q.At the upper end of each rack q is provided a roller or rollers r, andover and in contact with the roller or rollers on each rack there ismounted on the upper transverse member c of the frame an angularlyadjustable ramp s. The two ramps 8 are oppositely inclined. During onemovement of the saddle e one of the ramps s, by its downward pressure onthe corresponding rack q, imparts an angular movement to the pinion p inthe one direction, and during the opposite movement of the saddle theother ramp imparts (in like manner) the opposite angular movement to thepinion. In the example shown the ramps .9 are provided on dis-likecarriers 1. which are supported by ball or roller bearings u on theadjacent ends of coaxial shafts 11 secured to the transverse framemember 0, clamping pieces as '10 being provided for securing thecarriers to the adjacent parts of the transverse frame member after theramps have been brought to the required adjusted positions by angularmovements of the carriers on their supporting shafts. For enabling suchmovements to be imparted to the carriers 25 an actuating member a: issecured at its inner end to one of the carriers, and extends at itsouter end through an arcuate slot y in a cover piece .2 closing anopening in the front of the transverse frame member 0 By moving theactuating member :1: along the slot y the carrier t secured to theactuating member can be moved angularly on its supporting shaft 11 foradjusting the corresponding ramp 3, and the adjusting movement of thisramp causes similar adjusting movement in the opposite direction to beimparted to the other ramp s through the racks q and pinion p.

The grinding wheel m is carried by a slide 2 which is verticallyadjustable on a vertical guide 3 under the action of a screw as l9, thelatter being operable by the attendant through either of a. pair of sandwheels 20, 2|, in the usual manner. The guide 3 depends from ahorizontal arm 4 which at one end is pivoted to a horizontally movableslide 5 on the upper frame member 0, and which at the other end ismovable along and securable in any desired position to a segmental guide6 on the latter slide, the arrangement being such that the arm isangularly adjustable about a vertical axis to enable the central planeof the grinding wheel m to be brought into any desired relationship withthe axis of the work piece 7c corresponding to the helix angle of theteeth to be ground. Rotation of the grinding wheel m is effected by anelectric motor I or other convenient means on the vertically adjustableslide 2 carrying the grinding wheel. Any convenient screw and nut orother means as 8 operable by an electric motor are provided for movingthe horizontally movable slide along the frame member 0.

The mechanism for trimming the grinding wheel m comprises a support 9mounted on the base a of the frame and adapted in any convenient mannerto be adjusted about a vertical axis, a horizontally movable slide I Ion the support, a pillar IS on the horizontally movable slide, avertically adjustable slide [4 on the pillar, and trimming tools l5 onthe upper end of the latter slide, any suitable means (not shown) beingprovided for imparting motions to the trimming tools corresponding tothe contours of the working faces of the grinding wheel. The pillar I3is slidable horizontally with the slide H and is also angularlyadjustable about a vertical axis with the support 9 so that the line oftravel of the pillar corresponds with the plane of the grinding wheel172. Any convenient hydraulic or other means as H3 are provided formoving the slide I l and pillar [3 towards and away from the grindingwheel 112. Moreover any convenient provision is made for verticaladjustment of the tools [5. Thus in the example shown, a non-rotatablescrew I! extends from the bottom of the slide 14, carrying the trimmingtools l5, and engages an axially immovable nut IS on the horizontallymovable slide H, so that rotation of the nut causes vertical adjustmentof the trimming tools.

When the machine above described is in operation the work piece It isreciprocated relatively to the rotating grinding wheel m and during eachreciprocation the work piece is also given the required angularmovements by the ramps 5 above-mentioned. After the grinding of anadjacent pair of tooth faces of the work piece It by the formed surfacesof the grinding wheel m,

the work piece is given an angular movement by the indexing mechanism inthe head stock it to bring the next pair of faces into position forgrinding. Feeding of the grinding wheel m towards the work piece k iseffected by the attendant through the means provided for verticallyadjusting the slide 2 carrying the grinding wheel. When trimming of thegrinding wheel m is required, the slide 5 carrying the arm 4 is movedfrom one of its end positions (determined by stops 22) on the upperframe member 0 to another, and the slide H of the trimming mechanism isthen advanced to bring the trimming tools l5 into their operativeposition. After trimming, the slide II is retracted and the slide 5 isreturned to its initial position.

By this invention I am able to provide a machine for grinding helicaltoothed wheels by means of a formed grinding wheel in a manner whichenables the required accuracy of work and convenience of manipulation tobe achieved in a very satisfactory manner.

The invention is not limited to the example above described assubordinate details may be varied to suit requirements.

Having thus described my invention what I claim as new and desire tosecure by Letters Patent is:

1. A gear grinding machine as claimed in claim 4, in which the means forimparting oscillatory movements to the work piece comprise thecombination of a spindle on the saddle which operates the work piece, apair of reciprocatory members operatively connected to the spindle, anda pair of ramps angularly adjustable on the frame, the ramps serving toimpart through the medium of the said reciprocatory members oppositeangular movements to thespindle during the reciprocation of the workpiece relatively to the grinding wheel.

2. A gear grinding machine as claimed in claim 4, in which the means forimparting oscillatory movements to the work piece comprise thecombination of a pinion on a spindle on the saddle which operates thework piece, a pair of vertical racks engaging opposite sides of thepinion, and a pair of ramps angularly adjustable on the frame, the rampsserving by co-operation with the racks to impart opposite angularmovements to the pinion during the reciprocation of the work piecerelatively to the grinding wheel.

3. A gear grinding machine comprising the combination of a rigidsupporting frame consisting of a base, end columns, and an uppertransverse member, with a bed on the base, a horizontally reciprocablesaddle mounted on the bed and adapted to carry the work piece, ahorizontally movable slide on the said transverse member, an arm mountedon the slide and capable of angular adjustment about a vertical axis,means for adjustably mounting a formed grinding wheel on the arm so thatangular adjustment of the arm enables the central plane of the grindingwheel to be moved to any desired position relatively to the axis of thework piece, a spindle mounted on the saddle and adapted to impartoscillatory movements to the work piece during the reciprocatorymovements of the saddle, a pair of vertically slidable racks engagingopposite sides of the pinion, and a pair of angularly adjustable rampsmounted on the said frame and adapted to co-operate with the racks forimparting opposite angular movements through the pinion to the spindleduring reciprocation of the saddle.

4. A gear grinding machine comprising the combination of a rigidsupporting frame consisting of a base, end columns, and an uppertransverse member, a horizontally movable slide on the transverse memberof the frame, an adjustable member carried by the slide and providedwith means for adjustably supporting a formed grinding wheel, the saidadjustable member being capable of angular adjustment about a verticalaxis to enable the central plane of the grinding wheel to be moved toany desired position relatively to the axis of the work piece, areciprocatory saddle on the base of the frame for carrying thework-piece, and means on the frame and saddle for imparting oscillatorymovements to the work piece during the reciprocatory movements of thesaddle.

ARTHUR HITCHCOCK ORCUTT.

